The contemporary art galleries are often called " white box " because their walls are usually painted white. Why those walls are white? Perhaps " white " is the symbol that means " nothing ", telling us " There is nothing but the art work in this gallery ". Then, why don't we paint it's floor white? Or, even if it's painted white, can we say " there's nothing on this floor" ? The floor receives gravity and enable the art work to exist in the gallery. At the same time, the audience is also received by the floor. He feels reaction from the floor, and is forced to be conscious of his body, that is to say, to feel " here I am ", even if there's no artwork. So the gallery owner. And this feeling would be more serious for him if there's no art work. The gallery floor would turn to be the ground where the reason of his existence is tested. This is the exhibition which expresses something like that.